Modify video_tag a bit and make audio_tag able to accept multiple sources

Handle nil in add_index :length option in MySQL

Our schema.rb is being generated with an `add_index` line similar to this:

    add_index "foo", ["foo", "bar"], :name => "xxx", :length => {"foo"=>8, "bar=>nil}

This is the same as it was on Rails 3.1.3, however, now when that
schema.rb is evaluated, its generating bad SQL in MySQL:

    Mysql::Error: You have an error in your SQL syntax; check the manual
    that corresponds to your MySQL server version for the right syntax
    to use near '))' at line 1: CREATE UNIQUE INDEX
    `xxx` ON `foo` (`foo`(8), `bar`())

This commit adds a check for nil on the length attribute to prevent the
empty parens from being output.

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

remove unnecessary AS::Concern usage

date_select fixes [3-2-stable]

Update time zone offset information

Please pull my changes - they fix a rare problem with tests framework

Use instance_eval instead of Proc#bind

quote fix ` to ' in the ArgumentError message

message quote fix

code improved with better condition

Fix broken build

Fix GH #4344. Callback defined in a module is not triggered when the module extends an object under Rails 3.2rc2

symbol nodes.  Fixes #4585

Proc#bind is not useful when called immediately and previous check for #call method is not correct

Don't type-cast unknown types to YAML.

let AR::Relation pretty_printed like an Array

Bump rubygems required version to 1.8.11 (default version in 1.9.3-p0)

Remove unused argument.

Remove not used if..else clause

Related to #4614.

alias_method added